Gardai have uncovered bizarre details of the lifestyle of the person being sought for questioning over the murder of homeless father-of-three Frankie Dunne (64).
Mr Dunne's headless body was found in the garden of a derelict house off Cork's Boreenmanna Road on Dec- ember 28.
Gardai have been trying to trace an eastern European man who is believed to have been in Mr Dunne's company on December 27.
The man left Ireland in the hours after Mr Dunne's body was found, travelling from Cork to Belfast and on to Edinburgh.
He is believed to have then flown to eastern Europe.
Garda inquiries have revealed that the man had been squatting in properties around Cork late last year after he had a row with his boyfriend and was forced to move out of the apartment they shared.
Detectives have discovered that the man - who worked in the catering industry - had been hiding in a loft over a restaurant which he had used as a temporary squat.
Staff at the restaurant were unaware he had been living in the roof space at night.
The man used holes in the ceiling to monitor movements around the property.
Further, he was also aware of the position of various security cameras.
CCTV footage showing him crawling around on the floor of the property in a bid to evade detection by the cameras has been seized by gardai.
It is believed to have been part of a bid to steal around €1,000, which he then used to fund his travel back to eastern Europe.
Clothing, footwear and a knife were recovered from the loft and are being examined by gardai.
The man has so far been described as "a person of interest" by detectives.
Gardai are expected to liaise with Interpol and Europol over tracing him.
One theory being examined is that Mr Dunne may have been attacked after a minor dispute over cash or alcohol escalated out of control.
He was described as "a gentleman" who was very quiet and best-known for his love of singing.
His headless body, which was also missing the arms, was discovered by a neighbour. The missing parts were later recovered in the garden.
The eastern European man left Cork on December 29.
A garda source said the investigation was "making substantial progress", with enormous support from the public.
Detectives believe Mr Dunne was murdered after a beating inflicted some time between December 27 and 28.
His family said "no one should have to endure such a terrible death".
"As Frankie's family, we hope no one else has to suffer the horrendous nightmare of what Frankie endured in the final hours of his life," they said.
"No one should be left so vulnerable on our streets.
"No one should ever be beaten or murdered because they find themselves helpless due to alcoholism or for any other reason."